The present invention relates to magnetic flowmeters used for measuring a fluid flow within a conduit, and more particularly to detection of low liquid conductivity or empty pipe conditions in magnetic flowmeters.
Generally, magnetic flowmeters measure a fluid flow rate by measuring a electric potential across two electrodes within the pipe segment, where the electric potential is induced within the flow by the presence of an electromagnetic field. The operating principle of the magnetic flowmeter is based on Faraday's Law of electromagnetic induction, which states that a voltage will be induced in a conductor moving through a magnetic field. The magnitude of the induced voltage is directly proportional to the velocity of the fluid flow, the width of the conductor, and the strength of the magnetic field.
Magnetic flowmeters may include circuitry and/or software for detecting empty pipe conditions. Unfortunately, under certain circumstances, empty pipe detection circuitry may still provide false indications of empty pipe conditions.
Therefore, there is an on-going need in the process industry for a magnetic flowmeter with improved empty pipe detection capabilities. Embodiments of the present invention provide solutions to these and other problems, and offer other advantages over the prior art.